feat(ui): searchable Material Design icon library for lists and folders

src/ClaudeDo.Localization/locales/de.json

@@ -473,6 +473,8 @@
       "sectionIcon": "ICON",
       "icon": "Listen-Icon",
       "iconHint": "Wird in der Seitenleiste neben dem Listennamen angezeigt.",
+      "iconSearchWatermark": "Alle Icons durchsuchen (Englisch, z.B. rocket, car, bug)",
+      "iconSearchTruncated": "Die ersten 200 Treffer werden angezeigt — Suche verfeinern.",
       "sectionAgent": "AGENT",
       "resetAgentSettings": "Agent-Einstellungen zurücksetzen",
       "sectionVerify": "VERIFIKATION",

src/ClaudeDo.Localization/locales/en.json

@@ -473,6 +473,8 @@
       "sectionIcon": "ICON",
       "icon": "List icon",
       "iconHint": "Shown next to the list name in the sidebar.",
+      "iconSearchWatermark": "Search all icons (English, e.g. rocket, car, bug)",
+      "iconSearchTruncated": "Showing the first 200 matches — refine the search.",
       "sectionAgent": "AGENT",
       "resetAgentSettings": "Reset agent settings",
       "sectionVerify": "VERIFICATION",

src/ClaudeDo.Ui/ClaudeDo.Ui.csproj

@@ -10,6 +10,7 @@
     <PackageReference Include="Avalonia" Version="12.0.4" />
     <PackageReference Include="Avalonia.AvaloniaEdit" Version="12.0.0" />
     <PackageReference Include="AvaloniaEdit.TextMate" Version="12.0.0" />
+    <PackageReference Include="Material.Icons" Version="3.0.2" />
     <PackageReference Include="TextMateSharp.Grammars" Version="2.0.3" />
     <PackageReference Include="CommunityToolkit.Mvvm" Version="8.4.1" />
     <PackageReference Include="Microsoft.AspNetCore.SignalR.Client" Version="8.0.11" />

src/ClaudeDo.Ui/Converters/IconKeyConverter.cs

@@ -2,27 +2,49 @@ using System.Globalization;
 using Avalonia;
 using Avalonia.Data.Converters;
 using Avalonia.Media;
+using Material.Icons;
 
 namespace ClaudeDo.Ui.Converters;
 
 /// <summary>
-/// Converts an icon key string (e.g. "Sun") to the matching StreamGeometry resource "Icon.Sun".
+/// Converts an icon key to its geometry: "Sun" → the "Icon.Sun" StreamGeometry resource,
+/// "mdi:RocketLaunch" → the Material Design Icons path of that <see cref="MaterialIconKind"/>.
 /// </summary>
 public class IconKeyConverter : IValueConverter
 {
+    /// <summary>Key prefix marking a Material Design Icons kind.</summary>
+    public const string MdiPrefix = "mdi:";
+
     public static IconKeyConverter Instance { get; } = new();
 
+    private static readonly Dictionary<string, Geometry?> MdiCache = new();
+
     public object? Convert(object? value, Type targetType, object? parameter, CultureInfo culture)
     {
         if (value is not string key || string.IsNullOrEmpty(key))
             return null;
 
+        if (key.StartsWith(MdiPrefix, StringComparison.Ordinal))
+            return MdiGeometry(key[MdiPrefix.Length..]);
+
         var resourceKey = $"Icon.{key}";
         if (Application.Current?.TryGetResource(resourceKey, null, out var res) == true)
             return res as StreamGeometry;
         return null;
     }
 
+    /// <summary>Parses (and caches) the geometry for an MDI kind name; null for unknown names.</summary>
+    private static Geometry? MdiGeometry(string name)
+    {
+        if (MdiCache.TryGetValue(name, out var cached))
+            return cached;
+        var geometry = Enum.TryParse<MaterialIconKind>(name, out var kind)
+            ? StreamGeometry.Parse(MaterialIconDataProvider.GetData(kind))
+            : null;
+        MdiCache[name] = geometry;
+        return geometry;
+    }
+
     public object ConvertBack(object? value, Type targetType, object? parameter, CultureInfo culture)
         => throw new NotSupportedException();
 }

src/ClaudeDo.Ui/ViewModels/Modals/ListSettingsModalViewModel.cs

@@ -2,12 +2,14 @@ using System.Collections.ObjectModel;
 using ClaudeDo.Data;
 using ClaudeDo.Data.Models;
 using ClaudeDo.Data.Repositories;
+using ClaudeDo.Ui.Converters;
 using ClaudeDo.Ui.Localization;
 using ClaudeDo.Ui.Services;
 using ClaudeDo.Ui.ViewModels.Agent;
 using ClaudeDo.Ui.ViewModels.Modals.Settings;
 using CommunityToolkit.Mvvm.ComponentModel;
 using CommunityToolkit.Mvvm.Input;
+using Material.Icons;
 using Microsoft.EntityFrameworkCore;
 
 namespace ClaudeDo.Ui.ViewModels.Modals;
@@ -132,7 +134,66 @@ public sealed partial class ListSettingsModalViewModel : ViewModelBase
         "Box", "Truck", "MapPin", "Camera", "Image", "Barcode", "Skull",
     ];
 
-    public ObservableCollection<string> Icons { get; } = new(IconOptions);
+    /// <summary>Cap on search hits so the picker's WrapPanel stays responsive.</summary>
+    public const int MaxIconResults = 200;
+
+    // One entry per distinct MDI icon; the enum carries aliases, all of which stay searchable.
+    private static readonly Lazy<(string Key, string Names)[]> MdiIndex = new(() =>
+        Enum.GetNames<MaterialIconKind>()
+            .GroupBy(Enum.Parse<MaterialIconKind>)
+            .Select(g => (IconKeyConverter.MdiPrefix + g.First(), string.Join(' ', g)))
+            .ToArray());
+
+    /// <summary>Picker items: the curated set, or MDI search hits once the search has 2+ characters.</summary>
+    [ObservableProperty] private IReadOnlyList<string> _icons = IconOptions;
+
+    /// <summary>Free-text filter over the MDI icon names (English).</summary>
+    [ObservableProperty] private string _iconSearch = "";
+
+    /// <summary>True when the search hit more than <see cref="MaxIconResults"/> icons.</summary>
+    [ObservableProperty] private bool _iconResultsTruncated;
+
+    // Separate from Icon: swapping Icons makes the ListBox push null here, which must not wipe the choice.
+    [ObservableProperty] private string? _selectedIconOption = DefaultIcon;
+
+    /// <summary>True for a curated key or an existing "mdi:" kind.</summary>
+    public static bool IsKnownIcon(string? key) =>
+        key is not null && (IconOptions.Contains(key)
+            || (key.StartsWith(IconKeyConverter.MdiPrefix, StringComparison.Ordinal)
+                && Enum.TryParse<MaterialIconKind>(key[IconKeyConverter.MdiPrefix.Length..], out _)));
+
+    partial void OnIconSearchChanged(string value)
+    {
+        var q = value.Trim();
+        if (q.Length < 2)
+        {
+            IconResultsTruncated = false;
+            // Keep a chosen MDI icon visible (and selected) in the curated view.
+            Icons = IconOptions.Contains(Icon) ? IconOptions : [Icon, .. IconOptions];
+        }
+        else
+        {
+            var hits = MdiIndex.Value
+                .Where(e => e.Names.Contains(q, StringComparison.OrdinalIgnoreCase))
+                .Select(e => e.Key)
+                .Take(MaxIconResults + 1)
+                .ToList();
+            IconResultsTruncated = hits.Count > MaxIconResults;
+            Icons = hits.Take(MaxIconResults).ToList();
+        }
+        SelectedIconOption = Icons.Contains(Icon) ? Icon : null;
+    }
+
+    partial void OnSelectedIconOptionChanged(string? value)
+    {
+        if (value is not null) Icon = value;
+    }
+
+    partial void OnIconChanged(string value)
+    {
+        if (!Icons.Contains(value)) OnIconSearchChanged(IconSearch);
+        else SelectedIconOption = value;
+    }
 
     // The shared agent-config editor (Model / MaxTurns / SystemPrompt / AgentFile),
     // scoped to this list (list → global inheritance).
@@ -174,7 +235,7 @@ public sealed partial class ListSettingsModalViewModel : ViewModelBase
         IsFolder = true;
         CanToggleFolder = false;
         Name = name;
-        Icon = IconOptions.Contains(icon) ? icon! : DefaultFolderIcon;
+        Icon = IsKnownIcon(icon) ? icon! : DefaultFolderIcon;
     }
 
     public async Task LoadAsync(
@@ -198,7 +259,7 @@ public sealed partial class ListSettingsModalViewModel : ViewModelBase
             FindingsTracked = findingsTracked;
             // An unknown/legacy key would leave the picker with no selection and silently reset the
             // icon on the next save — fall back to the default instead.
-            Icon = IconOptions.Contains(icon) ? icon! : DefaultIcon;
+            Icon = IsKnownIcon(icon) ? icon! : DefaultIcon;
             WorkingDir = workingDir ?? "";
             DefaultCommitType = string.IsNullOrWhiteSpace(defaultCommitType) ? CommitTypeRegistry.DefaultType : defaultCommitType;
 

src/ClaudeDo.Ui/Views/Modals/ListSettingsModalView.axaml

@@ -143,8 +143,13 @@
           <ScrollViewer>
             <StackPanel Spacing="8" Margin="0,8,0,0">
               <TextBlock Classes="field-label" Text="{loc:Tr modals.listSettings.icon}"/>
+              <TextBox Text="{Binding IconSearch}"
+                       Watermark="{loc:Tr modals.listSettings.iconSearchWatermark}"/>
+              <TextBlock Text="{loc:Tr modals.listSettings.iconSearchTruncated}"
+                         IsVisible="{Binding IconResultsTruncated}"
+                         Opacity="0.6" FontSize="12" TextWrapping="Wrap"/>
               <ListBox ItemsSource="{Binding Icons}"
-                       SelectedItem="{Binding Icon, Mode=TwoWay}"
+                       SelectedItem="{Binding SelectedIconOption, Mode=TwoWay}"
                        Background="Transparent" BorderThickness="0"
                        HorizontalAlignment="Left">
                 <ListBox.ItemsPanel>
@@ -157,6 +162,7 @@
                     <!-- No Foreground here on purpose: the icon inherits the container's, so the
                          selected/hover states of ListBoxItem reach it (see Ui/CLAUDE.md). -->
                     <PathIcon Width="20" Height="20" Margin="6"
+                              ToolTip.Tip="{Binding}"
                               Data="{Binding Converter={StaticResource IconKey}}"/>
                   </DataTemplate>
                 </ListBox.ItemTemplate>

tests/ClaudeDo.Ui.Tests/ViewModels/ListSettingsModalViewModelTests.cs

@@ -74,6 +74,27 @@ public class ListSettingsModalViewModelTests
         Assert.Equal("Star", vm.Icon);
     }
 
+    [Fact]
+    public void IconSearch_FindsMdiIcons_AndClearingKeepsTheChoice()
+    {
+        var vm = new ListSettingsModalViewModel(new CountingWorker(), NewFactory());
+
+        vm.IconSearch = "rocket";
+        Assert.Contains("mdi:RocketLaunch", vm.Icons);
+        Assert.DoesNotContain("Star", vm.Icons);
+
+        vm.SelectedIconOption = "mdi:RocketLaunch";
+        vm.SelectedIconOption = null; // what the ListBox pushes when Icons is swapped
+        Assert.Equal("mdi:RocketLaunch", vm.Icon);
+
+        vm.IconSearch = "";
+        Assert.Equal("mdi:RocketLaunch", vm.Icons[0]);
+        Assert.Equal("mdi:RocketLaunch", vm.SelectedIconOption);
+
+        Assert.True(ListSettingsModalViewModel.IsKnownIcon("mdi:RocketLaunch"));
+        Assert.False(ListSettingsModalViewModel.IsKnownIcon("mdi:NoSuchIcon"));
+    }
+
     [Fact]
     public async Task LoadAsync_CallsGetListConfig_ExactlyOnce()
     {